Denmark’s Wozniacki was barely troubled by world number 101 Alexandrova as she converted five out of six break points to win her first claycourt match of the season in 68 minutes.
The reigning Australian Open champion, back in Istanbul after four years, next meets the winner of Wednesday’s match between Kirsten Flipkens and Sara Errani.
“It was tricky, for sure,” Wozniacki said. “The first match on clay is never easy, but I’m happy with the win. It’s great just to get a match in and feel better with the movement. It’s all about fine-tuning in matches like these.
“I’m using this as a preparation for the next few weeks, because the French Open is obviously around the corner. There’s lots to look forward to, and I want to keep feeling like I’m getting into the groove on clay.”
Earlier, world number 54 Donna Vekic advanced after Agnieszka Radwanska retired due to a back injury. Croatia’s Vekic was leading 6-1 2-0 when third seed Radwanska said she could not continue.
Zhang Shuai was stunned by Dutch qualifier Arantxa Rus 6-2 6-3 while Kazakhstan’s Yulia Putintseva fought back to get past sixth seed Sorana Cirstea 0-6 6-1 6-0.
Seventh seed Irina-Camelia Begu saved four set points in the opening set before moving past Slovenian qualifier Dalila Jakupovic 7-5 6-0. She meets America’s Christina McHale next.